Sorry if I don´t get it, but as in my last post:
Can you explain which settings these are on this screenshot? I know something in the DB, but what exactly?
I would have thought you just have the DB, connected the MX to one of the LAN ports of DB - forwarded 500/4500 to the MX (Lan Port or IP).
And another time, what about the packetcaptures on MX regarding to the ports 500/4500 as @ww mentioned.
Network Wide - packet capture
Instead of wireshark you can view the output below as well.
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